Russian hackers affiliated with the Killnet group executed a DDoS cyber attack that rendered 20 Japanese government websites inaccessible, including a tax and an e-Government portal.
The recent cyber attacks on Ukraine appeared to use distributed denial of service (DDoS) techniques to take several government websites offline for several hours.
Russia's current conflict with Ukraine is so far playing out with cyber attacks rather than physical warfare. A series of defacement attacks on government websites appears to be the opening salvo.